EnerSys and its predecessor companies have been manufacturers of industrial batteries for over 100 years. The current company was formed in late 2000 to acquire from Yuasa Corporation (Japan) its reserve power and motive power battery businesses in North and South America.

The company markets and sells reserve power batteries and motive power batteries under a variety of brand names including but not limited to PowerSafe, DataSafe, Hawker, & IRONCLAD.